The present invention relates to an antislip apparatus for footwear.
It is known to be quite difficult to walk on surfaces having low coefficient of friction, such as frozen grounds, roadways and sidewalks.
To overcome this problem, the prior art has provided shoes with rubber soles with marked protrusions or engravings. Such shoes, although having a sufficient grip on fresh snow, do not provide a safe hold in case of frozen surfaces.
An alternative to this solution is represented by metal, crampon-like prongs to be applied to the shoes. This solution provides a good grip but results in a bulky structure and makes it necessary to add an accessory to the shoes which thus cannot be used as a shoe.
The object of the present invention is to provide an apparatus able to provide a sufficient grip on slippery grounds for footwear of a sport type as well as for footwear of traditional type for everyday use.
This result has been achieved, according to the invention, by providing an apparatus having prongs for engaging the ground surface, a cam means for moving the prongs between a grip position with the prongs extending beyond the level of an engagement surface and a rest position with the prongs disposed inwardly of the engagement surface and an actuator or operating means connected to the prong drive for operating the cam drive. The actuator has an actuating interface accessible from the engagement surface side of the antislip apparatus.
A support for the prongs may be provided. The cam drive may include a cam interacting with the support so as to vertically move the prongs. The support may comprise an annular body having slots as well as solid lengths located along a circular crown. The slots may be angularly correlated to the prongs, the prongs being disposed perpendicular to the support.
The cam drive may comprise a plate disposed substantially parallel to the support and being led with one or more cams to interact either with the slots or with the solid lengths so as to vary the distance between the support and the plate thereby moving the one or more prongs.
The cam drive may comprise a plate and the actuator may include a substantially cylindrical rotor integral with the plate and having the actuating interface at a lower end thereof comprising a seat defined by a groove or cut.
The cam drive may include a plate with a central square bore and the actuator may include a rotor with a corresponding square portion for a stable coupling with the plate.
The antislip apparatus preferably includes a box element, wherein the plate and the support are disposed inside the box element, the plate being located above the support. An elastic means may be provided for providing and elastic connection acting between the box element and the support, the elastic means imparts a thrust in a direction opposite to the action exerted by the one or more cams on the support upon interaction by the one or more cams with the solid lengths. A cover may be provided closing the box element and having a pin on a lower face of the cover. The pin may be inwardly of the apparatus, the plate being rotatable relative to the cover and exhibiting a curved slot inside which the pin is inserted to define an extent of travel of angular displacement corresponding to a preset rotation of the cover with respect to the plate. The plate may include a central square bore and the rotor may include a corresponding square portion for a stable coupling with the plate.
The support may be made up of an annular, substantially flat body. The prongs may be arranged as angularly equidistant prongs extending perpendicularly from the flat body along a circular crown, saw slots may be connected between the prongs through flaring ramps.
The advantages of the present invention lie in that the antislip apparatus provides a suitable grip on the ground and is fully integrated with the shoe. The apparatus is undetectable by anyone looking at the shoe so that it can be used on traditional and/or elegant footwear. The apparatus is disposed as a box-like element so that it can be easily and quickly associated to the shoe and for this reason allows also a mass production for great number of shoes. The apparatus can be very well integrated in the shoe, without any part protruding from the shoe (in non-operative condition of the apparatus) and without any part able to damage itself and other objects. The apparatus is of simple and ready utilization; exhibits a robust structure and is able to maintain its features also after a prolonged wear. Another advantage lies in that it is possible to manufacture (and to mass-produce) heels (and/or soles) containing the antislip apparatus and the antislip apparatus is able to be utilized in the manufacture of shoes of sport type as well as shoe of a traditional type for everyday use, without modifying the structure of the shoes.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of this disclosure. For a better understanding of the invention, its operating advantages and specific objects attained by its uses, reference is made to the accompanying drawings and descriptive matter in which a preferred embodiment of the invention is illustrated.